Evaluation of the Vickers microhardness and fracture toughness on hot pressed Bi-2212/Ag ceramic composites

Kahraman, Funda

doi:10.1007/s10854-016-4796-7

Cited by 7 publications

(4 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, the standard error is very small, being, in some cases, lower than the symbols sizes. On the other hand, the hardness is clearly depending on the applied load, decreasing when the load is increased, in agreement with the typical behaviour reported in other TE or related ceramic materials [30][31][32].…”

Section: Resultssupporting

confidence: 90%

Effect of alkaline earth dopant on density, mechanical, and electrical properties of Cu0.97AE0.03CrO2 (AE = Mg, Ca, Sr, and Ba) delafossite oxide

et al. 2018

View full text Add to dashboard Cite

CuCrO 2 and Cu 0.97 AE 0.03 CrO x (AE=Mg, Ca, Sr, and Ba) polycrystalline materials have been prepared through the classical solid state route. CuCrO 2 is the major phase in all cases, with larger grain sizes when the alkaline earth dopant is larger. Doping also promotes the formation of secondary phases, which appear in the grain boundaries in the Ca, Sr, and Ba doped samples. Density has been drastically improved through doping, reflected in lower electrical resistivities and higher mechanical properties than the measured in undoped samples. In spite of a relatively high decrease of Seebeck coefficient, all doped samples reached higher power factor values than the undoped ones in the whole measured temperature range. The highest power factor has been reached in Mg doped samples, 0.32mW/K 2 m at 800ºC, which is among the highest obtained so far in randomly oriented polycrystalline CuCrO 2 materials.

show abstract

Section: Resultssupporting

confidence: 90%

Effect of alkaline earth dopant on density, mechanical, and electrical properties of Cu0.97AE0.03CrO2 (AE = Mg, Ca, Sr, and Ba) delafossite oxide

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The other bulk samples prepared show the moderate H v parameters between the values mentioned above. The similar ISE results (decrease in Vickers microhardness parameters with the applied test loads) can extensively encountered in the scientific studies in the literature [42]. It is possible to observe the typical ISE behaviors for other different superconducting parents of Cu-diffused bulk MgB 2 and Sm123 1−x Nd123 x [43][44][45].…”

Section: Vickers Hardness Measurement Resultssupporting

confidence: 77%

Evaluation of load-independent microhardness values in Plateau regions of Vanadium substituted Bi-2212 ceramics

Ülgen¹,

Okur²,

Erdem³

et al. 2022

Phys. Scr.

View full text Add to dashboard Cite

This study reveals extensively effect of homovalent V/Bi partial replacement in Bi2.0-xVxSr2.0Ca1.1Cu2.0Oy ceramic matrix (0.00≤x≤0.30) on the key mechanical design performance parameters and load-independent Vickers microhardness parameters in plateau limit region by means of experimental microhardness tests and semi-empiric approaching models. It is found that the vanadium substitution level of x=0.01 is observed to be optimum amount in the Bi-2212 crystal lattice for refinement of fundamental mechanical properties due to the enhancement in stabilization of durable tetragonal phase, surface residual compressive stress and elastic recovery mechanism. Conversely, from the replacement level of x=0.01 onwards, the lattice strain field and stress concentration sites enhance significantly depending on the increase of microscopic structural problems, interaction problems between adjacent layers and crack-initiating flaws in Bi-2212 ceramic system. Correspondingly, stress-induced phase transformation begins to play predominant role, and excess vanadium substituted ceramic materials are easily broken at relatively smaller test load. Moreover, the models indicate that every ceramic compound shows standard indentation size effect (ISE) feature due to predominant behavior of elastic recovery in crystal structure. Hence, presence of optimum vanadium ions strengthens typical ISE characteristic behavior. Furthermore, among semi-empirical models the indentation-induced cracking (IIC) model exhibits the highest performance to inspect real microhardness values of Bi2.0-xVxSr2.0Ca1.1Cu2.0Oy ceramic compounds in the plateau limit region.

show abstract

“…As it can be clearly observed in the graph, the hardness is clearly depending on the applied load, decreasing with logarithmic trend with the load. This behaviour is the typical determined in similar ceramic systems [29,30]. The data were analysed according to Meyer's law [31]:…”

Section: Results and Discusionmentioning

confidence: 91%

High mechanical and thermoelectric performances in hot-pressed CdO

Madre

Torres

Sotelo

2016

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

High density bulk CdO polycrystalline thermoelectric ceramics have been prepared through a hot-pressing process. Density measurements have revealed that density reaches 99.5 % of the theoretical one, in agreement with the observed microstructure. Microhardness has shown to have indentation size effect, decreasing when the load is raised. Electrical resistivity shows metalliclike behaviour until 650 ºC and semiconducting-like at higher temperatures while Seebeck coefficient increases in the metallic-like region and decreases in the semiconducting one. The maximum power factor values, 1.6 mW/K 2 m, have been achieved at about 650 ºC. These values are the highest obtained in this family of materials, with the advantage of its low thermal treatment duration, when compared with the typical solid state sintering process.

show abstract

Evaluation of the Vickers microhardness and fracture toughness on hot pressed Bi-2212/Ag ceramic composites

Cited by 7 publications

References 25 publications

Effect of alkaline earth dopant on density, mechanical, and electrical properties of Cu0.97AE0.03CrO2 (AE = Mg, Ca, Sr, and Ba) delafossite oxide

Effect of alkaline earth dopant on density, mechanical, and electrical properties of Cu0.97AE0.03CrO2 (AE = Mg, Ca, Sr, and Ba) delafossite oxide

Evaluation of load-independent microhardness values in Plateau regions of Vanadium substituted Bi-2212 ceramics

High mechanical and thermoelectric performances in hot-pressed CdO

Contact Info

Product

Resources

About